Added documentation about default values

README.md

@@ -78,31 +78,52 @@ user.api_attributes # => {...}
 
 ### Default values
 
-You can easily setup default values for your attributes by passing `:default` option to `attr` method.
+Attrio supports all the ways to setup default values that Virtus has.
 
 ```ruby
-class User
+class Page
   include Attrio
-	
+
   define_attributes do
-  	attr :name, String, :default => 'John Doe'
-    attr :age, Integer, :default => 18
-    attr :birthday, DateTime
+    attr :title, String
+
+    # default from a singleton value (integer in this case)
+    attr :views, Integer, :default => 0
+
+    # default from a singleton value (boolean in this case)
+    attr :published, Boolean, :default => false
+
+    # default from a callable object (proc in this case)
+    attr :slug, String, :default => lambda { |page, attribute| page.title.present? ? page.title.downcase.gsub(' ', '-') : nil }
+
+    # default from a method name as symbol
+    attr :editor_title, String,  :default => :default_editor_title
+  end
+
+  def initialize(attributes = {})
+    self.attributes = attributes
+  end
+
+  def attributes=(attributes = {})
+    attributes.each do |attr,value|
+      self.send("#{attr}=", value) if self.respond_to?("#{attr}=")
+    end
+  end
+
+  def default_editor_title
+    if self.published?
+      title
+    else
+      title.present? ? "UNPUBLISHED: #{title}" : "UNPUBLISHED"
+    end    
   end
 end
-```
 
-```ruby
-user = User.new
-user.age
-# => 18
-user.name
-# => 'John Doe'
 ```
 
 ### Methods visibility
 
-Don't want your accessors to be public? This behaviour can be overridden easily. 
+Don't want your accessors to be public? Visibility can be overridden easily. 
 
 ```ruby
 class User

lib/attrio/attribute.rb

@@ -30,7 +30,7 @@ def instance_variable_name
 
     def default_value
       if !defined?(@default_value)
-        @default_value = Attrio::DefaultValue.new(self.klass, self.name, (self.options[:default] || self.options[:default_value]))
+        @default_value = Attrio::DefaultValue.new(self.klass, self.name, self.options[:default])
       end
       @default_value      
     end

lib/attrio/reset.rb

@@ -14,12 +14,12 @@ def define_attrio_reset(as)
         end  
 
         define_method "reset_#{as.to_s}_defaults" do |attributes = []|
-          self.send(as.to_s, attributes).values.select(&:default_value).each { |attribute| self.send(attribute.writer_method_name, nil) }
+          self.send(as.to_s, attributes).values.select{ |attribute| !attribute.default_value.nil? }.each { |attribute| self.send(attribute.writer_method_name, nil) }
           self.send("set_#{as.to_s}_defaults", attributes)          
         end
 
         define_method "set_#{as.to_s}_defaults" do |attributes = []|
-          self.send(as.to_s, attributes).values.select(&:default_value).each do |attribute|
+          self.send(as.to_s, attributes).values.select{ |attribute| !attribute.default_value.nil? }.each do |attribute|
             next if self.send(attribute.reader_method_name).present?
 
             default_value = attribute.default_value.is_a?(Attrio::DefaultValue::Base) ? attribute.default_value.call(self) : attribute.default_value